Punching tool assembly

ABSTRACT

A punch-member holder and drive assembly for being reciprocated in a guide portion of a punch press, said assembly comprising a body guided by said guide portion for reciprocation, the body having a lower surface engageable with the punch member and an inner locating surface also engaging the punch member, and releasable gripping means carried by the body for latching onto a head of the punch member.

, United States Patent Inventor DennisDaniels Wi1liamsvl|1e,N Y.

Appl. No. 11,639

Filed Feh.16, 1970 Division of Ser. No. 696,027, Jan. 5, 1968, now Patent No. 3,530,750, which is a continuation-impart of application Ser. No. 629,335, Feb. 6, 1967, now Patent No. 3,449,991, which is a continuation in-part of application Ser. No. 528,856, Feb. 21, 1966, now abandoned.

Patented Aug. 24, 1971 Assignee Houdallle Industries, Inc. Buffalo, N.Y.

PUNCHING TOOL ASSEMBLY 5 Claims, 2 Drawing Figs.

Int.Cl B261 1/14 [50] Field of Searchnu, 83/698, 571, 616, 684, 686; 279/37, 89, 90

[56 References Cited UNITED STATES PATENTS 1,671,369 1928 Johann 83/616 X 2,567,605 1951 Kean 279/37 2,614,781 1952 Engel 279/37 X 3,495,493 2/1970 Herb et aL 83/698 Primary ExaminerAndrew R. Juhasz Assistant ExaminerJames F. Coan Attorney-Hill, Sherman, Meroni, Gross & Simpson ABSTRACT: A punch-member holder and drive assembly for being reciprocated in a guide portion of a punch press, said assembly comprising a body guided by said guide portion for reciprocation, the body having a lower surface engageable with the punch member and an inner locating surface also engaging the punch member, and releasable gripping means carried by the body for latching onto a head of the punch member.

Patented Aug. 24, 1971 flk/ ATTORNEYS INVENTOR PUNCHING TOOL ASSEMBLY RELATED APPLICATIONS This application is a division of my copending application, Ser. No. 696,027, filed Jan. 5, 1968, now US. Pat. No. 3,5 30,750, which in turn is a continuation-in-part of my application for U8. patent on a PUNCH PRESS, filed Feb. 6, 1967, Ser. No. 629,335, now US. Pat. No. 3,449,991, which was a continuation-in-part of my application for US patent on a PUNCH PRESS, filed Feb. 21, 1966, Ser. No. 528,856, which is now abandoned.

BACKGROUND OF THE INVENTION Field of the Invention The present invention is directed to a punch drive assembly to which a punch and stripper sleeve may be readily attached and detached.

SUMMARY OF THE INVENTION A punch drive assembly is provided with gripping means for latching onto a head of a punch member to form a rigid connection therewith.

Accordingly, it is an object of the present invention to provide a punch drive assembly which will enable rapid loading or unloading of tooling used in association therewith.

Another object of the present invention is to provide a punch drive assembly which can be utilized with interchangeable tooling having standardized interfitting portions.

A still further object of the invention is to provide a punch drive assembly of a standard dimension for connection to a tool assembly having a standardized outer dimension with interchangeable punches and dies of different cutting dimensions.

Many other advantages, novel features and additional objects of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying sheets of drawings in which preferred structural embodiments incorporating the principles of the present invention are shown by way of illustrative example.

ON THE DRAWINGS FIG. 1 is a fragmentary cross-sectional view of a tool assembly constructed in accordance with the principles of the present invention disposed in a press; and

FIG. 2 is a cross-sectional view of the tool assembly of FIG. 1, with portions in elevation, arranged as a nested unit.

AS SHOWN ON THE DRAWINGS The principles of this invention are particularly useful when embodied in a tool assembly such as illustrated in FIG. 2 and generally indicated by the numeral 10. The tool assembly includes a punch member 11 nested in a stripper sleeve 12 and a die member 13.

. The punch member 11 has a body portion 14 which terminates at one end in a punch tip 15. At an end opposite the punch tip 15, the body 14 has an attachment means or structure generally indicated at 16 which includes a head portion 17 and a neck portion 18 of a reduced diameter which interconnects the body portion 14 to the head portion 17. The punch member 11 has a pair of oppositely facing abutments 19 and 21 on a shoulder or annular flange 22. The body portion is also provided with a locating means such as a pin 23 which insures the desired angular alignment of the punch with respect to a press.

The stripper sleeve 12 comprises a cylindrical hollow tube 24 having a stripper plate 25 disposed at one end and an upper retainer 26 disposed at the other end. The punch body portion 14 is movable axially with respect to the stripper sleeve 12 by an amount which is determined by the abutments 19, 21 which coact with the retainer 26 and the stripper plate 25 which provides an axial lost-motion connection therebetween, generally indicated at 20. The retainer 26 is an annular ring 27 received in an annular groove 28 on the inner surface or wall 29 of the sleeve 24. The stripper plate 25 has an aperture 31 in which the punch tip 15 projects with clearance so that the punch may move or reciprocate freely through the aperture 31.

The inner wall 29 has an enlarged portion or counterbore 32 which terminates at an internal shoulder or abutment surface 33. Disposed in the enlarged portion 32 is the stripper plate 25 with its upper peripheral surface 34 in contact with the shoulder 33.

To maintain the plate 25 in the enlarged portion 32, a lower resilient split ring 35 extends between a peripheral groove 36 in the plate 25 and an aligned annular groove 37 in the surface of the enlarged portion 32. The ring 35 may be contracted into the groove 36 to allow the removal of the stripper plate 25 from the enlarged portion 32 to facilitate removal of the punch member 1 1. When the plate 25 is placed in the enlarged portion 32 and the ring 35 is released, the ring expands into the groove 37 and extends across both the grooves 36 and 37 to hold the stripper plate 25 in the stripper sleeve 12.

The die member 13 has a cup-shape with a thick cylindrical wall 38 and a bottom 39. The bottom 39 has a workpiece-engaging surface 41 and a die aperture 42 which is complementary to the punch tip 15.

The tool assembly 10, when removed from a punch press, has the punch member 11 resting on the stripper plate 25 with the punch tip 15 extending through the aperture 31 of the stripper plate 25 and into and through the die aperture 42 of the die member 13. Gravity holds the parts assembled as shown, and gravity acts to shift the stripper sleeve by the amount permitted by the lost-motion connection 20, when the parts are installed in a press as shown in FIG. 1.

The tool assembly 10 is used in a punch press and is particularly useful in a turret press fragmentarily illustrated in FIG. 1 and generally indicated at 43. The turret press 43 has an upper turret generally indicated at 44 and a lower turret generally indicated at 45. The upper and lower turrets 44 and 45 are spaced apart to provide a space for a workpiece or sheet to pass therebetween. The turrets 44 and 45 are each provided with a plurality of aligned tool stations 46 and 47, respectively. The station 46 of the upper turret 44 is an inner cylindrical surface 48 of a sleeve-49 which is disposed in a cylindrical opening 50, and the station 47 of the lower turret 45 is a cylindrical opening 51 which has a diameter greater than the diameter of the cylindrical surface 48. The opening has a counterbore 52 which receives a flange 53 of the sleeve 49 to prevent the sleeve from movingtoward the turret 45.

The die member 13 is received in the opening 51 and has a locating means such as a pin 54 disposed in a passageway or bore 55 in the wall 38. The pin 54 is received in a groove 56 in the opening 51 to insure the correct angular alignment of the die member 13 in the turret press 43. The die member 13 and station 47 have a detent 57 to hold the die member 13 vertically, which detent includes a groove or depression 58 which receives a ball 59 which is urged by a spring 60 into engagement with the depression 58.

The stripper sleeve 12 and the nested punch member 11 are disposed in the station 46 with the stripper sleeve 12 having a loose fit with the cylindrical surface 48. The stripper sleeve 12 and the punch member 11 are held in the station 46 by a punch drive assembly generally indicated at 61 which is connected to a ram 62 of the turret press 43.

The punch drive assembly 61 has a housing or body portion 63 with an outer surface 64 which is complementary to the cylindrical surface 48. The punch drive assembly 61 is disposed in the sleeve 49 with the outer surface 64 slidably received by the cylindrical surface 48 to guide vertical movement of the punch drive assembly 61 in the station 46.

The housing portion 63 has an internal cavity 65 in which a gripping means generally indicated at 66 is disposed. The gripping means 66 includes a pair of arms 67, 67a each of which is pivotally mounted to the housing portion 63 by a pin 68. The arms 67, 67a each have an inwardly extending tip portion 69 which engages a bottom surface 70 of the head portion 17 of the attachment means 16. Each of the arms 67, 67a is urged inwardly toward the other arm by a spring 71 which extends between each arm 67, 67a and the housing portion 63.

The housing portion 63 has a lower portion 72 which extends past the tips 69, 69 and has an inner surface 73 that encircles and engages a surface 74 of the punch member 11 to guide the punch member against horizontal movement. The lower portion 72 terminates in a lower surface 75 which contacts the abutment surface 21 to transmit movement of the punch drive assembly 61 to the punch member 11. The surface 75 has a groove 76 to receive the pin 23 to insure angular alignment between the punch member 1 1 and the punch drive assembly 61.

The punch drive assembly 61 has a locating pin 77 which is received in an axially extending groove 78 in the cylindrical surface 48 to prevent rotation of the punch drive assembly 61. The sleeve 49 and the punch drive assembly 61 have a detent 79 which is similar to the detent 57 and is located in the flange 53 to hold the punch drive assembly 61 in an upper position illustrated in FIG. 1.

The housing portion 63 of the punch drive opposite the lower portion 72 has a head portion 80 which includes a pair of oppositely facing grooves 81, 81 and a pair of oppositely extending flanges 82, 82. The ram 62 has a pair of undercuts 83, 8 3 and a pair of inwardly extending flanges 84, 84 which are both complementary to and receive the grooves 81, 81 and the flanges 82,82 to form a connection between the ram 62 and the punch drive assembly 61 which becomes disconnected in response to the turrets 44 being rotated with respect to the ram 62.

The ram 62 as illustrated is a ram for a tool loading/unloading station and is provided with an ejection pin 85 which is relatively movable in the vertical direction with respect to the ram 62. The pin 85 has a pointed tip 86 and each of the arms 67, 67a are provided with a cam surface 87 which coacts with the tip 86 to move the arms 67, 67a outwardly to disengage the tips 69, 69 from the head portion 17 of the attachment means 16. To prevent accidental ejection of the punch member 11, one of the arms 67 is provided with lock means 88, 48 comprising a stop or projection 88 which contacts the cylindrical surface 48 when the arms 67, 67a are moved outwardly by the ejection pin 85. When the punch drive assembly 61 is moved vertically to a loading/unloading position in the station 46, the stop or projection 88 is received in a depression 89 provided in the cylindrical surface 48 of the sleeve 49 and the arms 67, 67a are both movable to be disengaged from the head 17 of the attachment means 16.

The head 17 of the attachment means 16 has a peripheral cam surface 90 which extends inwardly to a diameter substantially equal to a reduced diameter of the neck portion at 91. The tips 69, 69 of the arms 67, 67a are each provided with a cam or taper surface 93 which is directed toward the lower portion 72 of the housing portion 72 and is complementary to the cam surface 90.

To perform a punching operation with the tool assembly 10 in the press 43, the stations 46, 47 are indexed to a punching ram which is similar in structure to the ram 62 and becomes connected to the head portion 80 of the punch drive assembly 61. The indexing of the stations 46, 47 also positions the station 47 over an apertured bolster plate which prevents the die member 13 from being forced from the station 47 during the punching operation, but allows passage through the aperture of the slug formed by the punching operation. The punch drive assembly 61 is moved toward the lower turret 45 by the punching ram and in turn forces the punch member 11 downwardly into contact with a workpiece positioned on the workpiece engaging surface 41. The stripper sleeve 12 moves with the punch member 11 until the stripper sleeve contacts the workpiece. To grip the workpiece between the stripper sleeve 12 and the surface 41 as the punch tip 15 is being punching ram to withdraw the punch tip 15 from the workpiece. During upward movement of the punch member 11, the stripper sleeve 12 is still urged against the workpiece to facilitate stripping of the punch tip therefrom. After the punch member 11 has been moved a distance provided by the lostmotion connection 20, the abutment surface 21 engages the retainer 26 to overcome the force applies by the stripper pins and carries the stripper sleeve 12 upwardly to the position illustrated in FIG. 1.

To unload a tool assembly 10 from the turret press 43, the stations 46, 47 are indexed to the tool loader/unloader ram 62 and a tool loader is positioned beneath the turret 45 under the station 47. Then the ram 62 moves the punch drive assembly 61 downwardly to the loading/unloading position to move the punch member 11 and stripper sleeve 12 toward the die member 13. With the punch drive assembly 61 at the loading/unloading station, the punch member 11, stripper sleeve 12 and die member 13 are nested together with the punch tip 15 extending into the die aperture 42. As illustrated, the die member is still held in the station 47 by the detent 57; however, the distance to the loading/unloading position for the punch drive assembly 61 could be selected so that the die member 13 would be forced from its position in the station 47 and supported by the tool loader. With the punch drive assembly 61 in the loading/unloading position, a downward movement of the ejection pin causes the arms 67, 67a to move outwardly to disengage from the head 17 of the attachment means 16 and to disconnect the punch member 11 from the punch drive assembly. Once disconnected, the punch member 11 slides downward until its movement is stopped by the die member 13. If the die member is still held in the station 47 by the detent 57, further downward movement of the ejection pin 85 will force the punch member 1 1, stripper sleeve 12 and die member 13 out of the stations 46 and 47 onto the tool loader. Or the ejection pin 85 is retracted to allow the arms 67, 67a to move downwardly past the loading/unloading position to push the tool assembly out of the stations onto the tool loader.

To load a tool assembly 10 into the turret press 43, the stations 46, 47 are indexed to the ram 62 and the punch drive assembly 61 is moved to the loading/unloading position. The tool assembly 10 is disposed on the tool loader which moves upwardly to place the tool assembly into the station 47. The tool loader continues to move the tool assembly upwardly until the cam surface of the head 17 of the die member cams the arms 67, 67a outwardly to allow the head to move past the tip portions 69, 69. Once the head 17 is past the tip portions 69, 69, the springs 71, 71 move the arms 67, 67a inward so that the tips 69, 69 engage the head 17. Then the punch drive assembly 61 moves upwardly to draw the punch member 11 further into the station 46. The abutment 21 engaging the retainer 26 causes the stripper ring 12 to move with the punch member 11 into the station 46. If the die member 13 was not seated in the station 47 while the punch member 11 was attached to the punch drive assembly 61, the tool loader moves the die member 13 upwardly until the ball 59 of the detent 57 engages the depressions 58 to insure the vertical position of the die member 13 in the station 47. The specific structure of the tool loader is the subject of other of my applications.

During all of the handling of the tool assembly 10, namely during loading and unloading, the punch member 11, stripper sleeve 12 and die member 13 are in a nested relation with the die tip 15 in the die aperture 42 thereby rendering it impossible where a noncircular or shaped punch tip is employed to angularly misalign the punch member 11 with respect to the die member 13.

Although various minor modifications might be made or suggested by those versed in the art, it should be understood that I wish to employ within the scope of the patent warranted hereon, all such embodiments as reasonably and properly come within the scope of my contribution to the art.

I claim as my invention:

1. A punch-member holder and drive assembly for being reciprocated in a guide portion of a punch press, said assembly comprising:

a. body means having an outer surface for being slidably guided by the guide portion of the punch press during reciprocation, said body means having a lower surface for transferring'the punching force to the punch member, and an inner locating surface for engaging a surface of the punch member, said body means having an internal cavity;

b. releasable gripping means carried by said body means and disposed in said cavity for latching onto a head of the punch member to form a rigid connection therewith; and

c. rigid lock means functionally filling a space adjacent to said gripping means and normally blocking radial movement of said gripping means for preventing release of the punch member, said gripping means being movable radially and hence released only when said lock means has been displaced from its space-filling position adjacent to said gripping means.

2. A punch-member holder and drive assembly according to claim 1, including in combination therewith a punch member having a body portion terminating in a punch tip at one end and having an abutment coacting with said lower surface, said punch member having attachment means including a head portion extending from said abutment away from said punch tip, said gripping means engaging said head portion and coacting therewith.

3. A punch-member holder and drive assembly according to claim 1, wherein said gripping means includes an arm having a tip portion at one end extending at an angle thereto, said arm being pivotally mounted at the other end, a spring biasing said arm into an engagement position, said am having a cam surface between said ends arranged so that a force applied to said cam surface causes said arm to be pivoted against said spring to a disengagement position.

- 4. A punch-member holder and drive assembly according to claim 3, wherein said lock means comprises a stop on said arm for coacting with the guide portion of the punch press to prevent said arm from pivoting to said disengagement position, and for being received in a depression in the guide portion to enable pivoting of said arm to said disengagement position when said stop is aligned with the depression.

5. A punch-member holder and drive assembly according to claim 3, wherein said tip portion has a cam surface facing away from said other end of said arm, said cam surface being engageable by the head of the punch member to pivot said arm against said spring to said disengagement position to enable insertion of the head of the punch member past said tip portion.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. Dated August 1971 Inventor(s) Dennis Daniels It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 4, l. 3 after "61" insert --force the stripper sleeve 12 against the workpiece. The stripper pins are urged or biased downwardly by springs or hydraulic systems such as described in my above-menti0ned United States Patent No. 3,449,991. After the punch member 11 has".

Signed and sealed this 18th day of April 1972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents 'ORM PO-1050 (10-6B) USCOMM-DC Bean-P69 Q \LS GOVERNMENT PRINTING OFFICE: I939 0-366-334 

1. A punch-member holder and drive assembly for being reciprocated in a guide portion of a punch press, said assembly comprising: a. body means having an outer surface for being slidably guided by the guide portion of the punch press during reciprocation, said body means having a lower surface for transferring the punching force to the punch member, and an inner locating surface for engaging a surface of the punch member, said body means having an internal cavity; b. releasable gripping means carried by said body means and disposed in said cavity for latching onto a head of the punch member to form a rigid connection therewith; and c. rigid lock means functionally filling a space adjacent to said gripping means and normally blocking radial movement of said gripping means for preventing release of the punch member, said gripping means being movable radially and hence released only when said lock means has been displaced from its spacefilling position adjacent to said gripping means.
 2. A punch-member holder and drive assembly according to claim 1, including in combination therewith a punch member having a body portion terminating in a punch tip at one end and having an abutment coacting with said lower surface, said punch member having attachment means including a head portion extending from said abutment away from said punch tip, said gripping means engaging said head portion and coacting therewith.
 3. A punch-member holder and drive assembly according to claim 1, wherein said gripping means includes an arm having a tip portion at one end extending at an angle thereto, said arm being pivotally mounted at the other end, a spring biasing said arm into an engagement position, said arm having a cam surface between said ends arranged so that a force applied to said cam surface causes said arm to be pivoted against said spring to a disengagement position.
 4. A punch-member holder and drive assembly according to claim 3, wherein said lock means comprises a stop on said arm for coacting with the guide portion of the punch press to prevent said arm from pivoting to said disengagement position, and for being received in a depression in the guide portion to enable pivoting of said arm to said disengagement position when said stop is aligned with the depression.
 5. A punch-member holder and drive assembly according to claim 3, wherein said tip portion has a cam surface facing away from said other end of said arm, said cam surface being engageable by the head of the punch member to pivot said arm against said spring to said disengagement position tO enable insertion of the head of the punch member past said tip portion. 